Methyl bromide is an effective fumigant used in controlling a large variety of soilborne pests. As methyl bromide is an ozone depleting agent, and further it is relatively toxic for humans, its use has been gradually reduced, and the demands for alternative pesticides have been increasing. A promising alternative for methyl bromide is 3-bromopropyne, usually called propargyl bromide (PB). PB may be prepared by the reaction of propargyl alcohol with PBr3 in the presence of pyridine, but the selectivity and yield of the reaction are low. U.S. Pat. No. 6,794,551 improved the process by controlling temperature and effecting the reaction under an inert atmosphere without the presence of a base. Another problem about PB is its high flammability, and its vapors may form explosive mixtures with air. Precariously, propargyl bromide is a shock- and temperature-sensitive material that may detonate. Several techniques addressed the problem and stabilized PB by admixing a solvent forming an azeotropic mixture with the PB (see WO2004/071192; U.S. Pat. No. 6,777,375; U.S. Pat. No. 6,825,390; U.S. Pat. No. 7,015,367). It is an object of the present invention to provide an industrial process for manufacturing propargyl bromide in a stable form and in a good yield.
It is another object of the present invention to provide a composition comprising propargyl bromide in a sufficiently high concentration for intended applications but without being impact sensitive.
It is still another object of the present invention to provide a composition comprising propargyl bromide which is not explosive on heating.
Other objects and advantages of present invention will appear as description proceeds.